When Snape catches Harry and Ron after they arrive at Hogwarts via flying car,   
   he claims that he doesn't have the power to expel them, since they are not of   
   his House, so he goes to fetch McGonagal and Dumbledore.  Not only can't Snape   
   expel Harry and    
   Ron, he doesn't even give them detention or take points off of them.  Would   
   that mean that Snape doesn't have the power to detain Harry and Ron or take   
   points off of them?  McGonagal does give them detention, but doesn't take   
   points off because Harry and    
   Ron had taken the flying car BEFORE the term started!   
      
   On many other occasions throughout the series, Snape does take points off of   
   and/or detains Harry, Ron, and other Gryffindors.  McGonagal takes points off   
   of and detains Draco Malfoy.   
      
   Book 6: Snape takes 70 points off of Harry when he arrives late for the   
   opening feast.  Why doesn't he take points off of Harry and Ron over the   
   flying car incident?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)